We've noticed recently (2-3 weeks) that stainless utensils are coming out of the dishwasher with rust spots. Could this be something with the dishwasher (we're thinking of getting a new one anyways), or could it be the dishwashing detergent? I've also notice some rust stains on the stainless interior of the dishwasher, but I thought it was just old stains. We're using Cascade Platinum gel packs.
Stainless steel that is washed while in contact with other alloys may rust or developed pitting due to galvanic interactions. You may want to be careful about keeping some space between the good cutlery and other kitchenware.
To remove the rust stains, if they won't easily polish off, I have become very fond of soaking in household vinegar. Iron oxide plus acetic acid yields water-soluble iron acetate, while unoxidized iron is mostly immune to the stuff
When purchasing you should look for a stamp that shows the chromium to nickel content. 18/8 or 304 is best to resist rust. I use 18/0 because I'm allergic to nickel so have to deal with some rust here and there. Higher nickel content will resist rust but generally costs more. If it isn't stamped to show the nickel content then it's likely very low/zero and cheap SS.
